Two words: Population Explosion.

To all the protesters who oppose marriage equality due to inability to reproduce: I have two points.

Firstly, there are far more than enough children in the world without more being born. Think of homosexuality as a natural form of birth control. Furthermore, allowing gay and lesbian couples to adopt children from poverty stricken countries and places where they would otherwise have a short or tragic life will cause a reduction in global overpopulation and poverty children.

Secondly, if you deny marriage to homosexuals due to inability to reproduce, you must also deny it to heterosexual couples too old to reproduce, couples who are infertile, and couples who choose not to have children.

My final point: Homosexuality is a natural form of childbirth. This is a form of social evolution that can lead to a cleaner earth, less overpopulation, and happiness for all.

An evolutionary basis for homosexuality,

I have heard one compelling argument for an evolutionary basis of homosexuality from a friend of mine. Evolutionary success depends on to components, survival and reproduction. Survival comes first because without it reproduction is impossible. As an organism you need not only yourself to survive, but also your children so that they can also reproduce. So there has to be this balance. On the one hand you want to have as many children as possible, and on the other hand you don't want to spread your resources too thin. The solution is homosexuality. As a parent (until recently) it was hard to predict which of your children would survive into adulthood. So you just had as many as you could. And at a rate of 2-3% there was a good chance that a handful of your offspring would be heterosexual. But if you were lucky, one of them would be homosexual. Why? Because as the childless "aunt" or "uncle" to your grandchildren, they would concentrate resources toward your grandchildren to increase their survival rate.

Evolution of society.

Until recently being gay has been stigmatised. It is only recently that it has become more acceptable. Because of this I think the gay population will reduce in number over the next few generations as there is much less pressure on gay people (in the west at least) to marry and have children in order to appear 'normal' as it was maybe a century ago. With gay marriages and such, gay people are much more open about their sexuality and are spending their lives with other gay people. This must surely result in a reduction of gay people reproducing.

Of course it is

Anatomy did not intend for the anus to be used as a vagina. Males are meant to be with females. Two men or two women together is unnatural and nature never intended for the same sex to have sex with each other. Homosexuality is a biological error that cannot be corrected.

It is a product of evolution (hear me out)

Homosexuality isn't hurting our population or our ability to procreate and survive. It is a product of the fact that humans have reached a point in space and time where many of us no longer are trying to "survive" but instead are seeking knowledge. Gay people have always exists in small numbers, just like a rare mutation does. However, since that mutation isn't a problem for the human race, it has continued to flourish. When the number of humans actually starts to drop, you'll see a heck of a lot less gay people being born. Homosexuality is a product of a successful species.

It's the product of being highly evolved (please hear me out)

Essentially, the human species has dominated the planet and we don't have any foreseeable problems with increasing the size of the human population. The amount of Homosexuality is a product of this rapid expansion. Homosexuality has always existed in rare circumstances, just like any disease. However, as we evolve and feel less of a need to procreate and just "survive" we are granted these types of freedoms. It's not about a choice to be gay. It's about a choice to be straight. As our population continues to grow, so will the percentage of homosexuals. It is a product of evolution.

Obviously homosexuality has been benefictial for evolution

Homosexuality might have been benefictial for their group or family. For a species to succeed it doesn't require that every individual reproduces (i.E. Only the queen bee reproduces, and infertile bees are necessary). Having no interest in the opposite sex is a serious default for an individual, if the purpose of im or her is reproducing. (purpose in the means of evolution). It might be the same for humans. What is the purpose of gay relationships? Well, maybe gay relatives took care of orphan children. Maybe they did better on their long lasting hunting trips, since they didn't lack sex. Maybe homosexual feelings tightent bonds between individuals who fought side by side, and ultimately led to them being more victorious fighters. What ever it ultimately is we have been Lucky to have genes that produce gay people every now and then. They have strenghtened our packs. Otherwise there wouldn't be so much love between all kinds of people, men, women, men and women.

IT HAS ALWAYS BEEN IN HUMAN CULTURE...AND THUS MUST BE COMPATIBLE WITH EVOLUTION. It exists extensively throughout the "animal kingdom" as well.

With all of the social bias and taboos against homosexuality in human culture, it is an absolute fact that homosexuality still exists. The reasons for it's survival throughout all of the evolution aren't clear at this time, but new science is uncovering more and more possibilities both physical and psychological. I don't see the importance or labeling it wrong or right. If a person is oriented one way why not believe them and let them live as they please? The only reason I can think of is losing precious genetic variations such as the genius of an Alan Turin or the many other traits that gay prodigies and the many gifts that have that will be lost to humanity if not brought back into the genetic pool. With 7 billion people, though, perhaps we have enough variability to let gay people just be gay and butt out of their lives.

Because gay is cool man

While it may not occur as frequently as heterosexuality, its part of a human in the same way. Even though evolutionary theory focuses on reproduction, evolution is responsible in some way for producing the quantity of homosexual individuals in the population. I believe that homosexuality is biological, and that people are born that way. Therefore it makes sense that those traits evolved in humans.

I believe homosexuality is part of evolution

We haven't always been an intellectual species, sex is to important for us to forget. We have sex to stop are species going extinct and mix the gene pool, the Ebola virus doesn't kill everyone. Imagine being an unintelligent species that only meets the same sex, homosexuality is useful for remembering what to do when we do meet the opposite sex.

Desire over Nature

It is not natural in a species to put the penis into the anus of another. Man chooses to do so out of desire not nature. Is it not natural for a male in a species to want feces/excrement or feces/excrement residue on his penis. Only humans choose to act contrary to natural desire.

Unfortunately it isn't.

The unfortunate aspect of homosexuality is that it is not compatible with evolution. The only way for a homosexual couple to procreate is by having a surrogate or by adoption. In the instance of two males, they would need a female counterpart to be a surrogate. With two females, they would need a male counterpart. In both instances, only one partner can be the biological parent of the child.

Evolution of society.

Until recently being gay has been stigmatised. It is only recently that it has become more acceptable. Because of this I think the gay population will reduce in number over the next few generations as there is much less pressure on gay people (in the west at least) to marry and have children in order to appear 'normal' as it was maybe a century ago. With gay marriages and such, gay people are much more open about their sexuality and are spending their lives with other gay people. This must surely result in a reduction of gay people reproducing.

No it isn't

If we are naturally selected then why would we have gays? If the goal for homosapiens is to reproduce why be gay? So you can't believe in the bible or quran and gay marriage nor can you believe in evolution and gay marriage. So can you believe with it? NOTHING!!!

Spontaneous ability to breed

Wouldn't we be seeing gay couples who are developing the ability to reproduce—even in small, Not functioning ways yet—by now? We've been evolving a long time now and surely organs in some gay people, Because of genes passed down from animals that have gay genes, Would start to develop the ability to procreate to continue the evolutionary process. But it isn't happening.

Evolution's processes would kill off homosexual genes.

Evolution is the passing down of the genes of those who survive and reproduce. Homosexuals don't reproduce and wouldn't spread genes. If it is a mutation, that's not the debate. Evolution would see a rapid elimination of homosexuality if it were passed down genetically. A gene that would limit the survival of a species even by a small percent would filter itself out.

Survival of the Fittest and Economics

It is simply true, based on economic competition and biological evolution, that it would be impossible to sustain a homosexual population. Such a population would prove to be a burden on society, as no genetic recombination would occur. Such genetic recombination, through reproduction, is crucial for evolutionary processes to occur. Thus, if you want to let the whole population to be afflicted with such an ideology and normal (but unfit) behavior, then you might as well call for the end of the human race!

It's a byproduct

Why does sex exist? Why are people monogamous? Homosexuality is likely a byproduct of sex existing; being pleasurable is incentive to reproduce. As a byproduct, people end up pair bonding in the wrong way. It's harmless, but doesn't advance the species. I'd argue heterosexual monogamy is the "anomaly" because it rules out sex just for pleasure and guarantees selection of the best genes. Heterosexuality is TOUGH. Especially considering men interact better with men and women interact better with women. Homosexuality should be normal because it's easier. However, for whatever reason (love, mental and chemical) we go out of our way to impress the opposite sex and attempt to prevent them from leaving to mate with other individuals.

Why not a byproduct?

Why does sex exist? Why are people monogamous? Homosexuality is likely a byproduct of sex existing; being pleasurable is incentive to reproduce. As a byproduct, people end up pair bonding in the wrong way. It's harmless, but doesn't advance the species. I'd argue heterosexual monogamy is the "anomaly" because it rules out sex just for pleasure and guarantees selection of the best genes. Heterosexuality is TOUGH. Especially considering men interact better with men and women interact better with women. Homosexuality should be normal because it's easier. However, for whatever reason (love, mental and chemical) we go out of our way to impress the opposite sex and attempt to prevent them from leaving to mate with other individuals.